The vasculosyncytial membrane (VSM), primary site of fetomaternal exchange is formed when syncytiotrophoblast surrounds the terminal villi and make a close contact with capillaries. Some syncytiotrophoblast forms thin single layer of villous and some syncytial nuclei become piled up to form the syncytial knots (SKs). Undoubtedly there is a clear-cut inverse relation between villous VSM and fetal hypoxia. In preeclampsia (PE) the hypoxia injury disrupts the syncytial architecture which in turn initiates other complications of PE. Present study was designed to observe the morphological and histomorphometric features of 84 placentas from control and PE (42 each) collected from Department of Obstetrics and Gynecology. Neonatal weight and placental weight were reduced in PE than the controls but the feto-placental index did not differ. The SK density and VSM thickness was found to be increased and was statistically significant in PE cases. In relation to SKs, the VSM thickness was twofold increased than the controls and was statistically significant. The SKs in the present study were classified as type-1, 2a, 2b, and 3. Type 1 was found to be 62% in control and 47% in PE, type 2a and 2b were 38% in control and 37% in PE, and type 3 was in 8% of PE cases. All the parameters of present study reveal the adverse effects of PE influencing on both morphological and microscopical features of the placenta resulting in fetal hypoxia.
Anoxia ; Capillaries ; Fetal Hypoxia ; Gynecology ; Membranes ; Obstetrics ; Placenta ; Pre-Eclampsia ; Trophoblasts

The vasculosyncytial membrane (VSM), primary site of fetomaternal exchange is formed when syncytiotrophoblast surrounds the terminal villi and make a close contact with capillaries. Some syncytiotrophoblast forms thin single layer of villous and some syncytial nuclei become piled up to form the syncytial knots (SKs). Undoubtedly there is a clear-cut inverse relation between villous VSM and fetal hypoxia. In preeclampsia (PE) the hypoxia injury disrupts the syncytial architecture which in turn initiates other complications of PE. Present study was designed to observe the morphological and histomorphometric features of 84 placentas from control and PE (42 each) collected from Department of Obstetrics and Gynecology. Neonatal weight and placental weight were reduced in PE than the controls but the feto-placental index did not differ. The SK density and VSM thickness was found to be increased and was statistically significant in PE cases. In relation to SKs, the VSM thickness was twofold increased than the controls and was statistically significant. The SKs in the present study were classified as type-1, 2a, 2b, and 3. Type 1 was found to be 62% in control and 47% in PE, type 2a and 2b were 38% in control and 37% in PE, and type 3 was in 8% of PE cases. All the parameters of present study reveal the adverse effects of PE influencing on both morphological and microscopical features of the placenta resulting in fetal hypoxia.
Anoxia ; Capillaries ; Fetal Hypoxia ; Gynecology ; Membranes ; Obstetrics ; Placenta ; Pre-Eclampsia ; Trophoblasts

No abstract available.
Anoxia* ; Neurons*

Unidirectional valve (UDV) malfunction causes rebreathing of expired gas during anesthesia. However, the resultant hypercarbia without hypoxemia by UDV malfunction is not easily detected. We experienced a case of severe hypercarbia which caused by sticking expiratory valve at 45 minutes after the induction of anesthesia, in spite of checking UDV function preoperatively. In this case, expiratory UDV malfunction was diagnosed with the change of capnographic waveform. And so, we recommend monitoring of capnographic waveform during every anesthesia, in addition to preoperative UDV checking.
Anesthesia ; Anoxia

BACKGROUND: The aim of the present study was to investigate the changes in the patterns of power spectrum of R-R interval variability on fetal lamb EKG during acute fetal hypoxia. METHODS: Acutely instrumented six fetal lambs during the third trimester of gestation(115 to 145 days) was subjected to reproducible hypoxia by reduction of maternal placental blood flow with complete obstruction of maternal abdominal aorta for 60 seconds. RESULTS: Power spectral density of low, middle and high frequency increased significantly on hypoxia compared to that of baseline state. Power density of high frequency was significantly higher than that of low and middle frequency in baseline state. And the power density of low and high frequency was significantly higher than that of middle frequency in hypoxic state and 1 minute of recovery. CONCLUSIONS: The conclusion is that an increase in power density of low frequency during hypoxia suggested increased sympathetic activity and increased power density of high frequency throughout the experimental procedures suggested active respiratory movements of fetal lambs close to term and increased parasympathetic activity, reflecting rapidly the autonomic nervous system changes of the fetal lambs.
Anoxia* ; Aorta, Abdominal ; Autonomic Nervous System ; Electrocardiography ; Female ; Fetal Hypoxia ; Heart Rate* ; Heart* ; Humans ; Pregnancy ; Pregnancy Trimester, Third

OBJECTIVE: To determine whether meconium staining can be the indicator of intrauterine hypoxia by comparing umbilical venous erythropoietin (EPO) concentration and the number of nucleated erythrocytes (NRBC), as a marker of intrauterine hypoxia, between non meconium-stained neonates and meconium-stained neonates of term pregnancy. And to determine correlation between the number of NRBC, EPO levels and interleukin-6 (IL-6), as another mediator of intrauterine hypoxia. METHODS: In 240 neonates with gestational age ranged from 37 to 41 weeks, including 231 cases of nonmeconium-stained neonates and 9 cases of meconium-stained neonates, we performed the measurement of EPO levels by RIA, the number of NRBC per 100 white blood cells (WBC) by blood smear and IL-6 by ELISA in umbilical venous blood at delivery. Statistical analysis was performed by chi-square test, Wilcoxon rank sum test, linear regression analysis using SPSS 11.0 version statistical package. RESULTS: Amniotic fluids of meconium-stained neonates had significantly greater EPO concentrations compared with that of nonmeconium-stained controls (41.3+/-13.0 vs 26.5+/-18.9 mIU/mL, p=0.001). But there were no statistical difference in the number of NRBC, IL-6 levels and hematocrit of umbilical venous blood. The EPO levels in umbilical venous blood was correlated with the number of nucleated erythrocytes (r2=7.7%, p<0.001), and IL-6 in umbilical venous blood was correlated with the number of NRBC. (r2=11.5%, p<0.001). CONCLUSION: These results suggest that meconium-stained amniotic fluid can be associated with fetal hypoxia. And the production of fetal NRBC is thought to be stimulated by EPO and IL-6, but it requires further study of other (yet to be determined) hypoxia-derived mediators.
Amniotic Fluid ; Anoxia ; Enzyme-Linked Immunosorbent Assay ; Erythroblasts ; Erythropoietin* ; Female ; Fetal Hypoxia ; Gestational Age ; Hematocrit ; Humans ; Infant, Newborn* ; Interleukin-6 ; Leukocytes ; Linear Models ; Meconium* ; Pregnancy*

OBJECTIVE: To determine the usefulness of neonatal nucleated red blood cell counts (nRBC) as an independent predictor of fetal hypoxia and perinatal outcome in severe preeclampsia. METHODS: One hundred thirty eight patients with severe preeclampsia were studied. Umbilical artery Dopppler velocimetry was performed in all patients, and were divided into two groups, the control group with present umbilical artery end diastolic velocity, and the case group with absent or reversed velocity. The patients were also separately grouped as another control (n=58), acute (n=19), and chronic hypoxia (n=55) according to abnormal Doppler findings, presence of oligohydramnios, intrauterine growth restriction (IUGR), and pattern of fetal heart rate tracings during labor. At delivery, the umbilical cord blood was collected and the levels of nRBC per 100 WBC were measured from the samples along with blood gas analysis. The results were compared between the control and acute groups, and chronic hypoxic fetus. Correlation with perinatal outcomes was also evaluated. Student's t-test, ANOVA, and regression analysis were performed for statistical analysis. RESULTS: Those with absent or reversed end diastolic velocity did not have significantly greater nRBC counts, but had lower platelet counts (p=0.02), lower pO2 (p=0.005), and higher pCO2 saturation levels (p=0.01). There were no significant differences with regard to nRBC counts among the control, acute, and chronic hypoxia groups. Elevated nRBC counts were significantly associated with neonatal intensive care unit stay of more than 28 days (p=0.013), respiratory distress syndrome (p=0.003), disseminated intravascular coagulopathy, or sepsis (p=0.041). CONCLUSION: nRBC counts did not show significant difference according to umbilical artery Doppler velocity. Also we could not find any difference between the control, acute, and chronic hypoxic group, suggesting that nRBC counts does not correlate with both hypoxic status, or duration of hypoxia. Correlation with elevated nRBC counts and neonatal intensive care unit stay of more than 28 days, respiratory distress syndrome, disseminated intravascular coagulopathy, and sepsis was observed. However, the overlapping results and the wide range of nRBC counts according to the complications limits its role as a predictor of poor perinatal outcome.
Anoxia ; Blood Gas Analysis ; Erythrocyte Count ; Female ; Fetal Blood ; Fetal Hypoxia* ; Fetus ; Heart Rate, Fetal ; Humans ; Infant, Newborn ; Intensive Care, Neonatal ; Oligohydramnios ; Platelet Count ; Pre-Eclampsia* ; Pregnancy ; Rheology ; Sepsis ; Umbilical Arteries

Anoxia ; Oxygen* ; Recovery Room*

Hypothesis that hypoxic tumors should be more responsive to the addition of preferential hypoxic cell cytotoxin SR 4233 (tirapazamine) to fractionated irradiation was tested in the mouse SCCVII carcinoma and RIF-1 sarcoma, Model of hypoxic tumor was established using the tumor bed effect; tumors growing in the preirradiated tissue (preirradiated tumors) were more hypoxic than tumors growing in the unirradiated tissue (unirradiated tumors). When the tumors reached a mean volume of 100 mmdegree, both unirradiated and preirradiated tumors were treated with a fractionated course of 62 Gy in 3 days or 8 2.5 Gy in 4days with SR 4233 (0.08 mmlo/kg/injuection) given 30 minutes before each irradiation or without SR 4233. Compared to the unirradiated tumors, hypoxic preirradiated tumors were approximately 5 times more resistant to fractionated irradiation alone but were approximately 5 times more responsive to SR 4233. Addition of SR 4233 potentiated the effect of fractionated irradiation in both unirradiated and preirradiated tumors. Potentiation in the preirradiated tumors was morequal to or greater than that in the unirradiated tumors and seemed to be higher for more fractionated treatment. We confirm the hypothesis in a transplantable mouse tumor. Present results suggest that radioresistance of some hypoxic tumors can be overcome with hypoxic cytotoxin.
Animals ; Anoxia ; Mice ; Sarcoma

Animals ; Anoxia* ; Muscles* ; Rats*